The use of cognition-enhancing drugs by heawdy individuaws in de absence of a medicaw indication spans numerous controversiaw issues, incwuding de edics and fairness of deir use, concerns over adverse effects, and de diversion of prescription drugs for nonmedicaw uses, among oders.[1][2] Nonedewess, de internationaw sawes of cognition-enhancing suppwements has continued to grow over time, exceeding US$1 biwwion in 2015.[3]

The word nootropic was coined in 1972 by a Romanian psychowogist and chemist, Cornewiu E. Giurgea,[4][5] from de Greek words νοῦς (nous), or "mind", and τρέπειν (trepein), meaning to bend or turn, uh-hah-hah-hah.[6]

The use of prescription stimuwants is especiawwy prevawent among students.[9] Surveys suggest dat 0.7–4.5% of German students have used cognitive enhancers in deir wifetimes.[10][11][12] Stimuwants such as dimedywamywamine and medywphenidate are used on cowwege campuses and by younger groups.[13] Based upon studies of sewf-reported iwwicit stimuwant use, 5–35% of cowwege students use divertedADHD stimuwants, which are primariwy used for enhancement of academic performance rader dan as recreationaw drugs.[14][15][16] Severaw factors positivewy and negativewy infwuence an individuaw's wiwwingness to use a drug for de purpose of enhancing cognitive performance. Among dem are personaw characteristics, drug characteristics, and characteristics of de sociaw context.[10][11][17][18]

The main concern wif pharmaceuticaw drugs is adverse effects, which awso appwy to nootropics wif undefined effects. Long-term safety evidence is typicawwy unavaiwabwe for nootropics.[13]Racetams — piracetam and oder compounds dat are structurawwy rewated to piracetam — have few serious adverse effects and wow toxicity, but dere is wittwe evidence dat dey enhance cognition in peopwe having no cognitive impairments.[19]

In de United States, dietary suppwements may be marketed if de manufacturer can show dat de suppwement is generawwy recognized as safe, and if de manufacturer does not make any cwaims about using de suppwement to treat or prevent any disease or condition; suppwements dat contain drugs or advertise heawf cwaims are iwwegaw under US waw.[20]

Eugeroics (armodafiniw and modafiniw) – are cwassified as "wakefuwness promoting" agents; modafiniw increased awertness, particuwarwy in sweep deprived individuaws, and was noted to faciwitate reasoning and probwem sowving in non-ADHD youf.[23] In a systematic review of smaww, prewiminary studies where de effects of modafiniw were examined, when simpwe psychometric assessments were considered, modafiniw intake appeared to enhance executive function, uh-hah-hah-hah.[27] Modafiniw does not produce improvements in mood or motivation in sweep deprived or non-sweep deprived individuaws.[28]

Caffeine – a meta-anawysis found an increase in awertness and attentionaw performance.[29][24]

"Piracetam is not a vitamin, mineraw, amino acid, herb or oder botanicaw, or dietary substance for use by humans to suppwement de diet by increasing de totaw dietary intake. Furder, piracetam is not a concentrate, metabowite, constituent, extract or combination of any such dietary ingredient. [...] Accordingwy, dese products are drugs, under section 201(g)(1)(C) of de Act, 21 U.S.C. § 321(g)(1)(C), because dey are not foods and dey are intended to affect de structure or any function of de body. Moreover, dese products are new drugs as defined by section 201(p) of de Act, 21 U.S.C. § 321(p), because dey are not generawwy recognized as safe and effective for use under de conditions prescribed, recommended, or suggested in deir wabewing."[33]

L-Theanine – A 2014 systematic review and meta-anawysis found dat concurrent caffeine and L-deanine use had synergistic psychoactive effects dat promoted awertness, attention, and task switching;[29] dese effects were most pronounced during de first hour post-dose.[29] However, de European Food Safety Audority reported dat, when L-deanine is used by itsewf (i.e. widout caffeine), dere is insufficient information to determine if dese effects exist.[34]

Panax ginseng – A review by de Cochrane Cowwaboration concwuded dat "dere is a wack of convincing evidence to show a cognitive enhancing effect of Panax ginseng in heawdy participants and no high qwawity evidence about its efficacy in patients wif dementia."[36] According to de Nationaw Center for Compwementary and Integrative Heawf, "[a]wdough Asian ginseng has been widewy studied for a variety of uses, research resuwts to date do not concwusivewy support heawf cwaims associated wif de herb."[37]

Ginkgo biwoba – An extract of Ginkgo biwoba weaf is marketed in dietary suppwement form wif cwaims it can enhance cognitive function in peopwe widout known cognitive probwems, awdough dere is no high-qwawity evidence to support such effects on memory or attention in heawdy peopwe.[38][39]

Sawvia officinawis (sage) – Some research has suggested certain extracts of Sawvia officinawis may have positive effects on human brain function, but due to significant medodowogicaw probwems, no firm concwusions can be drawn, uh-hah-hah-hah.[40][41] The dujone present in Sawvia extracts may be neurotoxic.[41]

Omega-3 fatty acids: DHA and EPA – two Cochrane Cowwaboration reviews on de use of suppwementaw omega-3 fatty acids for ADHD and wearning disorders concwude dat dere is wimited evidence of treatment benefits for eider disorder.[42][43] Two oder systematic reviews noted no cognition-enhancing effects in de generaw popuwation or middwe-aged and owder aduwts.[44][45]